Apparatus and method for generating three-dimensional image

Abstract

The present invention provides a depth image generation apparatus comprising: a light source for generating light to be emitted toward an object in order to solve an SNR problem caused by resolution degradation and an insufficient amount of received light, while not increasing the amount of emitted light when photographing a remote object; a first optical system for emitting, as a dot pattern and at the object, the light generated by the light source; an image sensor receiving the light reflected by the object, so as to convert the received light into an electrical signal; an image processor for acquiring depth data through the electrical signal; and a control unit connected to the light source, the first optical system, the image sensor and the image processor, wherein the control unit controls the first optical system so as to scan the object by moving the dot pattern in a preset pattern.

What is claimed is: 
     
       1. An apparatus for generating a depth image, the apparatus comprising:
 a light source configured to generate light; 
 a first optical system configured to direct the light generated by the light source toward an object in a dot pattern; 
 an image sensor configured to receive light reflected from the object and convert the received light into an electrical signal, wherein the image sensor comprises one or more receiving elements each corresponding to a divided region of a projection area of the dot pattern; 
 an image processor configured to obtain depth data from the electrical signal; and 
 a controller operably connected to the light source, the first optical system, the image sensor, and the image processor, 
 wherein the controller is configured to: 
 control the first optical system to scan the object by moving the dot pattern according to a predetermined pattern, 
 control the image processor to obtain the depth data based on location information about the dot pattern, wherein the location information comprises information about points to which one or more dots of the dot pattern are emitted; and 
 control the image processor to divide each divided region into subregions and obtain depth data for each of the subregions. 
 
     
     
       2. The apparatus of  claim 1 , wherein the first optical system comprises:
 a collimator lens configured to collect the light emitted from the light source and direct the light in a parallel direction; 
 a diffraction optical element configured to direct the light from the collimator lens toward the object in the dot pattern; and 
 an actuator configured to control movement of the dot pattern. 
 
     
     
       3. The apparatus of  claim 2 , wherein the actuator comprises one of a voice coil motor, a liquid lens, or a microelectromechanical systems (MEMS) scanner. 
     
     
       4. The apparatus of  claim 1 , wherein a number of subregions for each divided region is based on a distance to the object, and wherein obtaining the depth data is based on the number of the subregions. 
     
     
       5. The apparatus of  claim 1 , wherein the controller is further configured to obtain the location information based on movement information of the actuator. 
     
     
       6. The apparatus of  claim 1 , wherein the image sensor comprises multiple arrays of receiving elements configured as a single photon avalanche diode (SPAD) array, and wherein the multiple arrays of receiving elements correspond to the dot pattern. 
     
     
       7. The apparatus of  claim 6 , comprising a second optical system configured to receive reflected light of the dot pattern by matching the light with the multiple arrays of receiving elements. 
     
     
       8. The apparatus of  claim 7 , wherein the light source is a vertical cavity surface emitting laser (VCSEL). 
     
     
       9. A method of controlling a device for generating a depth image, the method comprising:
 emitting light toward an object in a dot pattern; 
 scanning the object by moving the dot pattern according to a predetermined pattern; 
 receiving light reflected from the object and converting the received light into an electrical signal, wherein the light is received via an image sensor comprising one or more receiving elements each corresponding to a divided region of a projection area of the dot pattern; and 
 generating depth data based on the electrical signal, 
 wherein the depth data is obtained based on location information about the dot pattern, 
 wherein the location information comprises information about points to which one or more dots of the dot pattern are emitted, and 
 wherein each divided region is divided into subregions and depth data is obtained for each of the subregions. 
 
     
     
       10. The method of  claim 9 , further comprising:
 obtaining an image to determine a distance to the object; and 
 configuring a number of the subregions based on the determined distance to the object.